Evaluation Of Genetic Variation Of Populus×Jianhumao And Research On The Tissue Culture Techniques

Populus×Jianhumao is a new poplar hybrid which was cultivated using the radioactive breeding by the College of Forestry in Gansu Agricultural University in the 1980s. It was obtained after intensity selecting, using P. nigra var. thevestina as the female parent, P. euphratica as the male parent and took P. tomentosa pollen radiation induction processing. Populus×Jianhumao's hybrid superiority is apparent. It not only has the characters of P. nigra var. thevestina's narrow shape and fast-growing, but also has the charactes of P. euphratica's bearing drought, resisting cold, bearing salt alkaloid and anti-pest. It is regarded as the first productive poplar variety which has P. euphratica's blood relationship in China, and it has strong adaptability in north China, especially in the northwestern region. This variety is popularized to the Hexi's partial areas and was considered as one of the main poplar new varieties since 1950s for its fine performance.In this paper, the genetic characteristic of Populus×Jianhumao was analyzed and its relationship to its parents was discussed on morphology and protein level by morphology observation, isozyme analysis. The purpose of the study is to provide a theory basis for selecting parents fast and reasonably. And it could enhance the validity, the reliability and the scientific tenability of intersection hybridization of poplar. Meanwhile, Populus×Jianhumao's tissue culture system was built by studying the tissue culture. It can provide the reference for its reserving method and rapid propagation and take this excellent variety popularized fast into application. The results showed as follows:1. According to phenotypic observation and leaf character analysis, Populus×Jianhumao prone to the female's heredity. But its charactes were better than P. nigra var. thevestina, especially in the growth quantity and the disease-resistant. It basically overcomed the female's flaws. Its crown showed as narrow and oval, straight truck, smooth bark, beautiful shape, and its hybrid superiority is apparent.2. According to phenotypic analysis of PER, EST, MDH, AAT, ADH and ME isozymes spectrum of Populus×Jianhumao and its parents, the hybrid owned both male and female characters enzyme band. It also had two or more than two same band compared with its parents. It was confirmed that Populus×Jianhumao was the hybrid of P. nigra...